Dana Milbank: Can Democrats keep it together?

For years, it was. But in the 2018 midterm elections, Democrats prevailed in the House because they managed to keep a singular and unrelenting focus on health care — refusing to take President Trump’s bait to engage in fights about MS-13, caravans, socialism, tax increases and other distractions du jour.

Since Democrats have finally found the formula for defeating Trump, now comes the most important question: Can they keep it together?

There will be an immediate clamor from the progressive base for impeachment proceedings and Medicare-for-all legislation, as well as votes on the guns, abortion, LGBTQ rights and immigration wish lists. Though oversight is important, there will be pressure for the party to consume itself with investigations of the president and multiple high-profile showdowns.

Democrats must resist this clamor. It is pointless to take up impeachment and single-payer health care and the like with Trump in the White House and his sycophants controlling the Senate. A GOP-style investigative orgy would help Trump politically by providing him an easy foil. This would jeopardize the people who gave the Democrats their majority — first-term Democrats from suburban swing districts. And it would deprive Democrats of their........